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A process for producing high purity silicon carbide uses a high purity tetraethoxysilane or the like as the silicon source and a novolak-type phenol resin or the like as the carbon source. The process comprises a step of forming silicon carbide in which silicon carbide powder is prepared by calcinin

A process for producing high purity silicon carbide uses a high purity tetraethoxysilane or the like as the silicon source and a novolak-type phenol resin or the like as the carbon source. The process comprises a step of forming silicon carbide in which silicon carbide powder is prepared by calcining a mixture of these sources in a non-oxidizing atmosphere, and a step of post-treating silicon carbide in which the silicon carbide powder thus obtained is treated by heating at a temperature of 2000.degree. to 2100.degree. C. for 5 to 20 minutes at least once while the silicon carbide powder is kept at a temperature of 1700.degree. or higher to lower than 2000.degree. C., to obtain silicon carbide powder having an average particle diameter of 10 to 500 .mu.m and a content of impurity elements of 0.5 ppm or less. The high purity silicon carbide powder is advantageously used as a material for producing an excellent silicon carbide single crystal having a decreased number of crystal defects.

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[ What is claimed is:] [1.] A process for producing high purity silicon carbide powder used for preparation of a silicon carbide single crystal comprising the steps of:forming silicon carbide in which silicon carbide powder is prepared by calcining, in a non-oxidizing atmosphere, a mixture obtained

[ What is claimed is:] [1.] A process for producing high purity silicon carbide powder used for preparation of a silicon carbide single crystal comprising the steps of:forming silicon carbide in which silicon carbide powder is prepared by calcining, in a non-oxidizing atmosphere, a mixture obtained by homogeneously mixing a silicon source which is one or more silicon materials selected from the group consisting of high purity tetraalkoxysilane, high purity tetraalkoxysilane polymer, and high purity silicon oxide, and a carbon source which is a high purity organic compound containing oxygen in the molecule thereof and giving residual carbon after being heated; andpost-treating silicon carbide in which the silicon carbide powder thus prepared is treated by heating the silicon carbide powder to a temperature of 2000.degree. to 2100.degree. C. for 5 to 20 minutes at least once while the silicon carbide powder is being maintained at a temperature of 1700.degree. or higher to lower than 2000.degree. C., to obtain silicon carbide powder having an average particle diameter of 10 to 500 .mu.m and a content of impurity elements of 0.5 ppm or less.